This happens to all lwjgl programs.It was also a great way to enable auto pilot in minecraft for a long time. (Holding a key when pressing ALT and releasing it before clicking the window covers the key release event)

I've got Windows 7, too. So far I thought that it might be a Windows thing which can't be reproduced with Linux, but if it works on your Windows, there must be a way to get it working on my computer too. At the moment I'm just using a different key for my game.

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